Construction toys in which three dimensional structures can be assembled from a quantity of individual blocks have been popular for many years. Some of these construction sets contain individual parts that are shaped like miniature bricks or blocks. These essentially three-dimensional construction elements are characterized by having a length, width and thickness that are all comparable. One-dimensional construction elements have a length that is significantly longer than the width and thickness. Building tiles are essentially two-dimensional structures having a thickness that is significantly smaller than the length or width. Some of these planar structures can be connected along edges to form three-dimensional assemblies. Mechanical interlocking structures have been employed to connect individual construction toy elements together, but there are generally restrictions on assembly geometries or critical alignment requirements, excessive connection forces and angles, or cost issues driven by dimensional fabrication precision requirements. Accordingly, a need exists for a robust construction toy system that is easy to assemble and take apart by children that is inexpensive enough to provide a sufficient number of parts to build a variety of three-dimensional structures.
In the prior art, magnets have been used to provide an easier assembly experience compared to some mechanical structures. The orientational character of magnetic poles may restrict how pieces may be combined. This attraction/repulsion characteristic may be useful for puzzles, but may not be desirable for providing flexibility in combining magnetic building elements into extended three-dimensional structures. Various techniques for overcoming magnetic polarity issues have been proposed including providing a plurality of magnetic poles in a plastic magnet, increasing the number of magnets, adding ferromagnetic structures lacking permanent magnetic poles or providing cavities to accommodate rotating magnets. These are not completely satisfactory for building extended structures from sub-assembled structures easily or for other cost or application reasons. Pole orientations that were once free to rotate when only two elements are brought together to form a subassembly, frequently do not rotate thereafter. This may prevent the attachment to other subassemblies in a predictable manner or at the desired position or orientation.
The use of rare earth or other strong magnets in toys has lead to safety concerns particularly with ingestion of multiple rare-earth magnets by young children. Even weaker and less expensive ceramic ferrite magnets in toys may still have safety issues with magnetic strength and exposed sharp edges due to their brittle nature.
Rubber bonded ferrite or plastic composite magnets are not brittle and have a relatively weak magnetic flux density. In children's toys, plastic magnet tape is typically used to hold small items to steel surfaces such as refrigerator doors in planar arrays. Multiple magnetic poles on one plastic magnetic tape surface may be formed to provide adequate holding strength in the direction across the thickness of the tape. The reaching strength of the magnetic attractive force away from this surface generally diminishes rapidly and is even lower in other directions. When plastic magnets are used in construction toys, they are generally designed to connect to a metal surface or each other only in direct and extended planar contact. Magnetic forces are typically insufficient to make attachments at a relative angle between the edges of building tiles using surface polarized plastic magnet tape.
A need exists for a construction toy system that overcomes one or more of these shortcomings.